In this work, we perform on-chip quantum random number generation (QRNG) that uses a novel differential amplifier configuration for conjugate homodyne detection. Leveraging separate integrated photonics and integrated analog circuit platforms, we present an alternative method for QRNG. This approach exploits the observable Z^, derived from the sum of squared conjugate quadrature distributions which we compare to the traditional single quadrature approach. Utilizing this method, we report a shot noise clearance (SNC) of 25.6 dB and a common mode rejection ratio (CMRR) of 69 dB for our homodyne detection system. We used a variety of design tools to model and predict performance and compare results with our measurements. The realization of our QRNG system consists of a 90{\deg} optical hybrid, a dual differential transimpedance amplifier (TIA), and a field-programmable gate array (FPGA) used for the real-time post-processing to produce a uniform random bitstream. The randomness extraction is implemented using a Toeplitz hashing algorithm and is validated by the National Institute of Standards and Technology (NIST) randomness test suites.
@article{arxiv.2412.02077,
title = {Integrated Differential Conjugate Homodyne Detection for Quantum Random Number Generation},
author = {Christian Carver and Jared Marchant and Benjamin Fisher and Nicholas Townsend and Tyler Stowell and Austin Barlow and Benjamin Arnesen and Shiuh-Hua Wood Chiang and Ryan M. Camacho},
journal= {arXiv preprint arXiv:2412.02077},
year = {2024}
}